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प्रश्न
Calculate the change in internal energy of a gas kept in a rigid container when 100 J of heat is supplied to it.
उत्तर
Given:-
Heat supplied to the system,
ΔQ = 100 J
Using the first law of thermodynamics, we get
\[∆ U = ∆ Q - ∆ W\]
Since the container is rigid, initial volume of the system is equal to the final volume of the system. Thus,
\[∆V=V_f - V_i=0\]
∆W = P
∆V = 0
∆U = ∆Q = 100J
We see that heat supplied to the system is used up in raising the internal energy of the system.
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